Ludwig Wittgenstein's father was Karl Wittgenstein who was Jewish while his mother was a Roman Catholic. Ludwig was baptised into the Catholic Church. His parents were both very musical and Ludwig was brought up in a home which was always filled with music, Brahms being a frequent guest. Ludwig's parents had eight children who were all highly gifted both artistically and intellectually. There were three girls, Gretl, Hermine, and Helene, and five boys Hans, Kurt, Rudolf, Paul, and Ludwig. The family were wealthy industrialists having made a fortune in the steel industry and, being one of the wealthiest families in Austria, they were able to provide the best possible education for their children.

Perhaps at this stage we should make some comments on Ludwig's brothers and sisters, for it will help to understand something of Ludwig's lifestyle as he grew up and also what he went through. Three of the boys, Hans, Kurt, and Rudolf, all committed suicide later in their lives. Paul was a talented pianist who lost an arm during World War I. Ravel composed Concerto for the Left Hand for him. Gretl had her portrait painted by Gustav Klimt, the great Austrian Art Nouveau painter. Hermine wrote an important article on Wittgenstein which is published in [16] and from which we give some quotes.

Ludwig was the youngest of the children and he was educated at home until he was fourteen years of age. He showed an interest in mechanical things as he grew up and when he was ten years old he made a working sewing machine. In 1903 Wittgenstein began three years of schooling at the Realschule in Linz, Austria, which specialised in mathematics and natural science. Coming from a cultured background into a school filled with working class children gave Wittgenstein a difficult and unhappy time. He did not understand his fellow pupils and to them he seemed [16]:-

... like a being from another world.

How could they be expected to understand the frail shy boy who spoke with a stammer, and whose father was one of the richest men in Austria? The school enhanced Wittgenstein's love of technology, however, and made him decide to study engineering at university. In 1906 he went to Berlin where began his studies in mechanical engineering at the Technische Hochschule in Charlottenburg. Intending to study for his doctorate in engineering, Wittgenstein went to England in 1908 and registered as a research student in an engineering laboratory of the University of Manchester.

His first project involved the study of the behaviour of kites in the upper atmosphere of the earth. He moved from this to further study of aeronautical research, this time examining the design of a propeller with a small jet engine on the end of each blade. At this stage Wittgenstein was much more practically minded than one might suppose, given his later highly theoretical work, and he not only studied the theoretical design of the propeller but he actually built and tested it.

The tests of the propeller were successful but, needing to understand more mathematics for his research, he began a study which soon involved him in the foundations of mathematics. Russell had published his Principles of Mathematics in 1903 and Wittgenstein turned to this work as he sought a better understanding of foundations of his subject. He became so interested in Russell's work that he decided that he wanted to learn more. Wittgenstein travelled to Jena to ask Frege's advice and was told that he should study under Russell.

Wittgenstein left his aeronautical research in Manchester in 1911 to study mathematical logic with Russell in Trinity College, Cambridge. Russell was not one to be easily impressed by a student, but he was certainly very impressed by Wittgenstein. Russell wrote that teaching Wittgenstein was:-

... one of the most exciting intellectual adventures [of my life]. ... [Wittgenstein had] fire and penetration and intellectual purity to a quite extraordinary degree. ... [He] soon knew all that I had to teach.

His disposition is that of an artist, intuitive and moody. He says every morning he begins his work with hope, and every evening he ends in despair.

By 1912 Russell had become convinced that Wittgenstein possessed a genius which should be directed towards mathematical philosophy. He therefore persuaded Wittgenstein to give up any ideas that he still had to resume his applied mathematical work on aeronautics.

The first paper that Wittgenstein presented was to the Cambridge Philosophical Society in 1912. Entitled What is philosophy [12]:-

... [it] shows that from the very beginning Wittgenstein recognised the importance of understanding the nature of philosophical problems and of reflecting on the appropriate methods for approaching them.

During this period at Cambridge, Wittgenstein continued to work on the foundations of mathematics and also on mathematical logic. He suffered depression, however, and threatened suicide on a number of occasions. He found Cambridge a less than ideal place to work since he felt that the academics there were merely trying to be clever in their discussions while their ideas lacked depth. When he told Russell that he wanted to leave Cambridge and go to Norway, Russell tried to dissuade him [14]:-

I said it would be dark, and he said he hated daylight. I said it would be lonely, and he said he prostituted his mind talking to intelligent people. I said he was mad, and he said God preserve him from sanity. (God certainly will.)

Despite Russell's attempts to stop him, Wittgenstein went to Skjolden in Norway and this proved an extremely fruitful period during which lived in isolation working on his ideas on logic and language that would form the basis of his great work the Tractatus Logico-Philosophicus. It was also a period when he continued to suffer depression. His letters to Hermine spoke of his mental torment (see [16]) and she wrote that during this time he lived:-

... in a heightened state of intellectual intensity, which verged on the pathological.

When World War I broke out in 1914 Wittgenstein immediately travelled from Skjolden to Vienna to join the Austrian army. He was keen to enlist since he wanted to face death [16]:-

Now I should have the chance to be a decent human being, for I'm standing eye to eye with death.

He served first on a ship then in an artillery workshop but he found his fellow soldiers very difficult as they subjected him to cruelty. In 1916 he was sent as a member of a howitzer regiment to the Russian front where he gained many distinctions for bravery. In 1918 he was sent to north Italy in an artillery regiment and he was there at the end of the war, becoming a prisoner of the Italians in Cassino. During these four years of active service Wittgenstein had written his great work in logic, the Tractatus, and the manuscript was found in his rucksack when he was taken prisoner. He was allowed to send the manuscript to Russell while he was held in a prison camp in Italy.

Having written what he believed was his final word on philosophy, Wittgenstein's intention was now to give up his study of the subject. Released from detention in 1919, he gave away the family fortune he had inherited and, in the following year, trained as a primary school teacher in Austria. He was trained in the methods of the Austrian School Reform Movement, which believed that the main aim of a teacher was to arouse a child's curiosity and to help the child develop as an independent thinker. The Movement rejected the method of teaching which encouraged children to simply learn to repeat facts. But although Wittgenstein was a strong believer in these principles and tried with great enthusiasm to provide the children that he taught in the mountain village of Wiener Neustadt with the best possible education, there were factors working against his success. Perhaps the biggest difficulty that Wittgenstein faced was that giving away the family fortune did nothing to enable someone with his highly privileged background to fit into the culture of the children of farmers who he taught.

During this period Wittgenstein was again desperately unhappy and came close to committing suicide on a number of occasions. The thought that he was appreciated by the children kept him at his task, but he found difficulties in keeping relations between himself and the other teachers on a friendly basis. Eventually, feeling largely that he had failed as a primary school teacher, Wittgenstein gave up in 1925. He still did not feel that he wanted to return to an academic life so he worked at a number of different jobs. First he worked as a gardener's assistant in the Hüsseldorf monastery near Vienna, living in the tool-shed for three months. Then he worked as an architect for two years occupied in the design and construction of a mansion house for his sister Gretl near Vienna.

Although Wittgenstein had not wished to return to academic life during this period he was not completely isolated from the study of mathematical logic, the foundations of mathematics, and philosophy. He met with Ramsey, who was making a special study of the Tractatus and had travelled from Cambridge to Austria on several occasions to have discussions with him, and he also met with philosophers from the Vienna Circle. There have been many theories put forward to explain why he returned to academic life, but at the heart of it must be that in the discussions he had, he came to see problems with the Tractatus.

In 1929 Wittgenstein returned to Cambridge where he submitted the Tractatus as his doctoral thesis. This work considers the relationship of language to the world. Words, Wittgenstein argued, were representations of objects and combining words led to propositions which were statements about reality, or as he says, pictures of reality. Such statements, of course, may picture a reality which is true or false. Conversely, the world as presented by Wittgenstein in the Tractatus, consists of facts. These facts can be broken down into states of affair, which in turn can be broken down into combinations of objects. This is essentially an atomic theory with the world built from simple objects. He argues that there is a bijection (one-one correspondence) between language and the world.

In the Preface to Philosophical Investigations written sixteen years after he returned to Cambridge, Wittgenstein wrote:-

... since beginning to occupy myself with philosophy again, sixteen years ago, I have been forced to recognise grave mistakes in what I wrote in that first book. I was helped to realise these mistakes - to a degree which I myself am hardly able to estimate - by the criticism which my ideas encountered from Frank Ramsey, with whom I discussed them in innumerable conversations during the last two years of his life.

However, it was not until 1953, two years after Wittgenstein's death, that this second great work Philosophical Investigations was published. In this work Wittgenstein studied [12]:-

... the philosophy of language and philosophical psychology. ... the form of the book is quite unique. ... we first get a part of 693 distinct, numbered remarks, varying in length from one line to several paragraphs, and a second part of fourteen sections, half a page to thirty-six pages long ... instead of presenting arguments and clearly stated conclusions, these remarks reflect on a wide range of topics without ever producing a clear final statement on any of them.

How does his approach in the Philosophical Investigations differ from that in the Tractatus? He is still concerned with language, but in his later thinking words are not unvarying representations of objects, but rather are diverse. He draws an analogy between words and tools in a tool-box:-

... there is a hammer, pliers, a saw, a screw-driver, a ruler, a glue-pot, nails and screws. The function of words are as diverse as the functions of these objects.

It was not that a word had a meaning, rather it had a use. Another illustration that he gives is an analogy between words and pieces in a chess game. The meaning of a chess piece is not determined by its physical appearance, rather it is determined by the rules of chess. Similarly the meaning of a word is its use governed by rules.

After the award of his doctorate, Wittgenstein was appointed a lecturer at Cambridge and he was made a fellow of Trinity College. In the following years Wittgenstein lectured there on logic, language, and the philosophy of mathematics. He was appointed to the chair in philosophy at Cambridge in 1939. Malcolm, a student of Wittgenstein, writes in [10] about Wittgenstein's lectures which he attended in 1939:-

His lectures were given without preparation and without notes. He told me once that he tried to lecture from notes but was disgusted with the result; the thoughts that came out were 'stale', or, as he put it to another friend, the words looked like 'corpses' when he began to read them. In the methods that he came to use, his only preparation for the lecture, as he told me, was to spend a few minutes before the class met, recollecting the course that the inquiry had taken at the previous meeting. At the beginning of the lecture he would give a brief summary of this and then he would start from there, trying to advance the investigation with fresh thoughts. ... [W]hat occurred in these class meetings was largely new research.

G H von Wright was a pupil of Wittgenstein at Cambridge. He writes [10]:-

Wittgenstein thought that his influence as a teacher was, on the whole, harmful to the development of independent minds in his disciples. I am afraid that he was right. And I believe that I can partly understand why it should be so. Because of the depth and originality of his thinking, it is very difficult to understand Wittgenstein's ideas and even more difficult t incorporate them into one's own thinking. At the same time the magic of his personality and style was most inviting and persuasive. to learn from Wittgenstein without coming to adopt his forms of expression and catchwords and even to imitate his tone of voice, his mien and gestures was almost impossible.

There is a suggestion here that Wittgenstein would never have fitted in as the leader of a large group of students and researchers. Although he did have students who went on produce important work, yet remain true to his way of thinking, Wittgenstein always seemed an isolated figure. He seemed to understand the reasons for this when he wrote:-

Am I the only one who cannot found a school or can a philosopher never do this? I cannot found a school because I do not really want to be imitated. Not at any rate by those who publish articles in philosophy journals.

Wittgenstein remained at Cambridge until he resigned in 1947 except for the period of World War II during which he worked as a hospital porter in Guy's Hospital in London. He also spent time working as a laboratory assistant in the Royal Victoria Infirmary before returning to his duties at Cambridge in 1944. After three years back at Cambridge he retired and moved to an isolated cottage on the west coast of Ireland. His health deteriorated and in 1949 cancer was diagnosed. Wittgenstein did not seem unhappy at the diagnosis since he said that he did not wish to live any longer. He continued to work on his ideas until a few days before his death, the power and depth of his intellect being undiminished by illness.

The power and originality of his thought show a unique philosophical mind and many would be happy to call him a genius.

Wittgenstein was never happy with his own writings and as a result only the one major work, the Tractatus, was published during his life. A wealth of material from his lectures and notes has subsequently been published. That his ideas are found difficult is something that he was well aware of and he felt that in some way he did not fit into the world in which he lived. Let us end with a quote from his own writing about why ideas are found difficult:-

Why is philosophy so complicated? It ought to be entirely simple. Philosophy unties the knots in our thinking that we have, in a senseless way, put there. To do this it must make movements that are just as complicated as these knots. Although the result of philosophy is simple, its method cannot be if it is to succeed. The complexity of philosophy is not a complexity of its subject matter, but of our knotted understanding.